Various medical devices, such as drug-coated balloons or stents, have been developed for localized drug delivery, for example immunosuppressive and/or anti-proliferative agents to target tissue within a body for treatment. However, the amount of drug transferred to the surrounding tissue is poorly controlled and highly variable.
For example, upon inflation of a drug-coated balloon in an artery, the drug is expelled from the balloon in the form of particulates, a majority of which tend to be flushed away by blood flow prior to the balloon surface engaging a surrounding tissue within an artery. Thus, only a small percentage (1-10%) of the drug is actually absorbed by the surrounding tissue. In addition, the balloon may inadvertently mobilize during the procedure to alter the drug dosage transferred to the surrounding tissue. Further, to compensate for the drug loss, the balloon may be coated with a high dose of the drug, raising concerns about toxicity and particularization. Thus, there is a need for improved systems and methods for controlled, localized delivery of drugs.